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Finding the Fourth Proportional to 405.23, 607.78 and 145.19

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Solution

The fourth proportional to 405.23, 607.78 and 145.19 is: 217.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.23 : 607.78 = 145.19 : x
  2. Step 2: Convert to fraction form
    405.23/607.78 = 145.19/x
  3. Step 3: Cross multiply
    405.23x = 607.78 × 145.19
  4. Step 4: Simplify right side
    405.23x = 88,240.18
  5. Step 5: Solve for x
    x = 88,240.18/405.23
  6. Step 6: Final answer
    x = 217.75

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.